Making initial checks on Linux

Before you start problem determination in detail on Linux®, consider whether there is an obvious cause of the problem, or an area of investigation that is likely to give useful results. This approach to diagnosis can often save a lot of work by highlighting a simple error, or by narrowing down the range of possibilities.

1. Identify characteristics of the problem
   There are some initial questions that you can consider to help you to identify the cause of the problem:

   • Has IBM MQ run successfully before?
   • Have any changes been made since the last successful run?
   • Have you applied any maintenance updates?
   • Has the application run successfully before?
   • Are you receiving errors when you use special characters in descriptive text for some commands?
   • Are there any error messages or return codes to help you to determine the location and cause of your problem?
   • Can you reproduce the problem?
   • Does the problem affect specific parts of the network?
   • Does the problem occur at specific times of the day?
   • Is the problem intermittent?
2. Investigate potential problems with applications, commands and messages
   If you encounter problems with IBM MQ applications, commands, and messages, there are a number of questions that you can consider to help you to determine the cause of the problem:

   • Are messages failing to arrive on the queue?
   • Do messages contain unexpected or corrupted information?
   • Are unexpected messages received when using distributed queues?
   • Have you received no response from a PCF command?
   • Are only some of your queues failing?
   • Does the problem affect only remote queues?
   • Is your application or system running slowly?
3. Investigate any problems connected to IBM MQ resources, including resource usage by IBM MQ processes, problems related to insufficient resources, and your resource limit configurations.
   For more information, see Additional checks for resource problems on Linux.
4. If you need further information to help you with identifying the cause of the problem, see Detailed troubleshooting.